c++ 随机生成带权联通无向图

提示

1、请使用 \(c++11\) 编译运行
2、默认生成 \(100\) 个输出文件，文件名为 \(data1.in\) 到 \(data100.in\)，如有需要自行修改
3、\(50000\) 以下的点 \(1s\) 内可以运行结束，\(50000-300000\) 的点在 \(30s\) 内运行结束， \(300000\) 以上看人品
4、生成的图为无向连通图，因此如果边数小于点数 \(-1\)，程序自动终止
5、如果边数点数大于 \(10000000\) 或者为负数，程序自动终止
6、如果运算量过大，程序自行终止
7、默认带有边权以及参数 \(k\)
8、\(4\) 到 \(7\) 条可以自行修改
9、输出到屏幕中的文字不会输出到文件中

代码

#include<bits/stdc++.h>
using namespace std;
#define rg register
const int maxn=1e7+5,maxm=1e3+5;
int n,m,cnt,fa[maxn];
char s[maxm][maxm];
int zhao(rg int xx){
    if(fa[xx]==xx) return xx;
    else return fa[xx]=zhao(fa[xx]);
}
int main(){
    fprintf(stderr,"This program is used to generate undirected connected graphs with n nodes, m edges and K weights.\n");
    fprintf(stderr,"The program generates 100 input files by default.\n");
    fprintf(stderr,"For each input file, you must enter three parameters, N, m, and K.\n");
    fprintf(stderr,"Please make sure that 0<=n<=10000000 0<=m<=10000000 m>=n-1.\n");
    fprintf(stderr,"N is the number of nodes in the graph, M is the number of edges in the graph\n");
    fprintf(stderr,"and K is some parameters in the graph. If you do not want to output K.\n");
    fprintf(stderr,"Please delete the code yourself.\n");
    default_random_engine engine(time(NULL));
    srand(time(NULL));
    for(rg int i=1;i<=100;i++){
        rg int cntt[9];
        memset(cntt,0,sizeof(cntt));
        rg int Num=-1,now=i;
        while(now){
            cntt[++Num]=now%10;
            now/=10;
        }
        s[i][0]='d',s[i][1]='a',s[i][2]='t',s[i][3]='a';
        for(rg int j=4;j<=Num+4;j++){
            s[i][j]=cntt[Num+4-j]+'0';
        }
        s[i][Num+5]='.',s[i][Num+6]='i',s[i][Num+7]='n';
    }
    for(rg int kk=1;kk<=100;kk++){
        long long now=0;
        if(kk>=2) fprintf(stderr,"Last num:%d is OK\n.",kk-1);
        fprintf(stderr,"Now the %dth set of data is generated.\n",kk);
        fprintf(stderr,"please enter n m k\n");
        fprintf(stderr,"And then waiting....\n");   
        freopen(s[kk],"w",stdout);
        cnt=0;
        rg int jl=0,n,m,k;
        scanf("%d%d%d",&n,&m,&k);
        uniform_int_distribution<> dis(1,0x3f3f3f3f);
        printf("%d %d %d\n",n,m,k);
        if(m<n-1){
            fprintf(stderr,"Wrong!m must be bigger than n-1.\n");
            fprintf(stderr,"The %dth data is not generated.\n",kk);
            continue;
        }
        if(m<0 || m>10000000){
            fprintf(stderr,"Wrong!m is too big or too small.\n");
            fprintf(stderr,"The %dth data is not generated.\n",kk);
            continue;
        }
        if(n<0 || n>10000000){
            fprintf(stderr,"Wrong!n is too big or too small.\n");
            fprintf(stderr,"The %dth data is not generated.\n",kk);
            continue;
        }
        for(rg int i=1;i<=n;i++) fa[i]=i;
        while(cnt<n-1){
            now++;
            if(now>=10000000000){
                fprintf(stderr,"Too large to build\n");
                jl=1;
                break;
            }
            rg int x=dis(engine)%n+1,y=dis(engine)%n+1,x1=zhao(x),y1=zhao(y),z=1LL*rand()*rand()%10000000+1;
            if(x1!=y1){
                fa[x1]=y1,cnt++;
                printf("%d %d %d\n",x,y,z);
            }
        }
        if(jl){
            fprintf(stderr,"The %dth data is not generated.\n",kk);
            continue;
        }
        m=m-(n-1);
        for(rg int i=1;i<=m;i++){
            rg int x=dis(engine)%n+1,y=dis(engine)%n+1,z=1LL*rand()*rand()%10000000+1;
            printf("%d %d %d\n",x,y,z);
        }
    }
    return 0;
}